There are three types of influenza virus: A, B, and C, which vary greatly in their epidemiological pattern. Influenza A virus is both the best characterized and the most serious threat to public health, capable of inducing massive epidemics or pandemics. This virus is also highly variable antigenically, making effective vaccine production difficult.
A vaccine to influenza would be one of the most efficacious, safe, nontoxic, and economical weapons to prevent disease and to control the spread of the disease. The primary aim of vaccination is to activate the adaptive specific immune response, primarily to generate B and T lymphocytes against antigen(s) associated with the disease or the disease agent.
Currently some vaccines against influenza are available and primarily consist of inactivated vaccines. These vaccines can comprise two type A antigens (e.g., H1N1 and H3N2) and one type B antigen. The available vaccines typically include whole virion, split-product, and subunit vaccines. Generally, these vaccines are effective in up to 90% of vaccinated individuals if the vaccines closely match the identity of the emerging epidemic. However, they need to be updated each year to keep pace with antigenic drift of the influenza virus.
Moreover, a cold-adapted live attenuated intranasal vaccine (LAIV) against seasonal influenza has been recently described. Cross-protective immunity was demonstrated in a study which reported protection against a H3N2 virus in cotton rats infected with a H1N1 strain. However, one major concern linked with LAIV is the possibility of genetic reversion and re-assortment with wild-type influenza viruses, resulting in a new, potentially infectious strain.
The invention addresses these and other problems in the influenza vaccine field by providing a vaccine and composition that elicits an immune response against one or more influenza strains using a mutated Bordetella strain as the active principle agent.
In addition, the related art describes various types of vaccines and compositions using Bordetella strains (WO2007104451 and WO2003102170) to induce immune responses against, e.g., Bordetella bacteria capable of causing whooping cough in humans; however the art fails to disclose methods or compositions for eliciting an immune response to an influenza virus in a mammal using the methods, compositions, and/or vaccines of the invention.
Thus, a need exists for a novel influenza vaccine capable of providing broad protection against diseases caused by influenza virus infection.